Structural element for buildings



Oct. 14, 1930. H. s. PRATT STRUCTURAL ELEMENT FOR BUILDINGS Filed Aug. 20, 1927 Patented Oct. 14, 1930 UNITED STATES PATENT OFFICE HAROLD G. PRATT, OI CLEVELAND HEIGHTS, OHIO, ASSIGNOB TO DETROIT STEEL PRODUCTS COMPANY, OI DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN STRUCTURAL ELEMENT FOR BUILDINGS Application filed August 20, 1927. Serial 1T0. 214,384.

- This invention relates to improvements in that class of structural building members or elements that are commonly known to the trade as metal timbers. Elements of this class are distinguished from ordinary I- beam or channels principally by the fact that they are made of sheet metal. 7

Among the objects which I have in view is to provide an element of the above mentioned class that is made of relatively thin sheet metal so as to minimize weight and cost and is of such cross section as will insure adequate strength and rigidity and permit of its production by standard methods and equipment.

Another object is to provide a structural element of the aforesaid class that is especially convenient of use in that it is designed to facilitate attachment to girders or other supports, and for quick and easy connection with parts supported by it, such as roof and floor plates.

A further and more limited object is to produce an element of the foregoing nature that is especially intended for use with sheet metal floor or roof plates of the ribbed type, an example of which will be found in Letters Patent No. 1,574,586 issued February 23, 1926, and to this end I provide the element with integral fastening means or prongs for holding engagement with said plates, there being preferably shouldered and non-shouldered prongs for use with said plates accordingly as the plates are applied tothe elements with their ribs toward or away from the same.

The foregoing and other objects are attained in the embodiment of the invention illustrated in the accompanying drawing wherein Fig. 1 is a fragmentary perspective view of my improved structural element; Fig. 2 is a similar view showing the element incorporated in a building construction; Fig. 3 is a transverse section through the element and includes associate-d parts of the building construction; and Fig. 4 is a view similar to Fig. 2 showing the ribbed plate inverted with respect to the position it occupies in Figs. 2 and 3.

The element, designated generally by the reference character A, is constructed of a single piece of sheet metal of suitable 'gage, the thickness of the metal depending upon the cross sectional size and the length of the element and the use to which it is to be put. The element consists of a base a, ,webs a that converge upwardly from the lateral edge portions of the base a, and flanges a" that extend outwardly from the upper edges of the webs a and are parallel with the lane of the base a. The outer edges of the anges a are preferably turned downwardly, as shown at a to impart strength and rigidity to said flanges.

The aggregate width of the flanges a is approximately equal to the width of the base a, and where the webs a join the base, the material is desirably turned over and inwardly upon the base a relatively short distance to provide what may be termed base flanges, the same being designated a.

Struck upwardly from the flanges a are prongs a and a", the former having shoulders a that are spaced above the plane of the flanges a a distance equal to or slightly greater than the length of the prongs a".

My improved building element is desi ned for use especially with floor and roof p ates of the kind disclosed in the above mentioned patent, and in Figs. 2, 3 and 4 the element is shown associated with such plates. Each of these plates, designated B, consists of a flat sheet of metal provided with hollow ribs Z) projecting from one face thereof, each of the ribs being substantially triangular in section with its base remote from the body of the sheet and connected to such sheet by convergent sides. The spacing of the shoulders at of the prongs a from the faces of the flanges a is substantially equal to the distance between the bases of the ribs 7) and the adjacent surface of the plate B.

In the incorporation of my improved structuralelement in building constructions, its ends are placed upon suitable supports, such as I-beam girders, a fragment of one of such girders being shown at C in Figs. 2 and 3. In order to hold the elements in place upon said girders, bolts or equivalent fastening means, designated D, are engaged If the construction is that of a roof, the

plates B are applied to the elements A with their ribs b engaging the flanges a. .When the plate is first placed in position it bears upon the points of'the prpngs a", and the workman then pounds the plate in the im'-.

mediate vicinity of said prongs until the prongs puncture the plate and project there.- above. The plate is then driven down upon the shoulders a and the ends of the prongs are turned over in the manner illustrated in Figs. 2 and 3.

In case the construction is that of a floor, the plates B are inverted so that their ribs 6 extend upwardly, and preparatory to applying the plates to the elements in this posi-' tion the prongs a are broken off or bent downwardly into the openings from which they were originally struck so that only the prongs a are left standing. The plate is brought to rest upon these prongs and by the same operation as that above described the prongs arecaused to penetrate the plate and are clinched thereabove so as to effectively secure the plate in immediate contact with the flanges a.

By reference to the aforesaid Patent No.

1,574,586 it will be seenv that suitable ma terial is applied to the top surfaces of the plates B in the completion of the roof or floor. v

Having thus described my invention, what I claim is:

1. A building element for use with ribbed plates, said'element having a-surface wherewith said plates are adapted to be engaged amass? from said surface of the element "a-distance I substantially equal to the depth of said ribs.

4 A buildin element for use with ribbed floor or roof p ates, said element consisting from the upper edges of the webs in a plane substantially parallel to the base, and prongs struck from said flan es and rojected upwardly, certain of sail? prongs aving shoulders spaced from the flan es a distance sub-- stantlally equal to that o? the depth of the ribs of said plates.

5. A building element for securing ribbed roof or floor plates to beams and consisting of a sheet metal member having a base, the lateral edges of which are turned inwardly to provide base flanges, the said element havmg webs converging upwardly from the lateral edge portions of the base and terminating in oppositely disposed flanges extending substantially parallel with the base flanges, the said lastmentioned flanges havmg prongs struck up therefrom, certain of said prongs having shoulders thereon and adapted for engagement with said plates to secure the same in place.

In testimony whereof, I hereunto aflix my signature.

HAROLD G. PRATT.

are spaced from said surface a distance sub-,

stantially equal to the depth of the ribs of said plates.

3. A building element foruse with ribbed floor or roof plates, said element being constructed of sheet metal and having a surface wherewith said plates are adapted to be engaged either with their ribs turned toward or away from said surface, and prongs struck from the materialof said element, certain of said prongs having shoulders spaced 

